Differential clutch



Jan, 6, 1925.

2 sheets-sheet 1 ffl/Iliff! {Iliff/.147.

T. J. SHANAHAN DIFFERENTIAL CLUTCH Filed March 28,

Patented Jan. 6, 1925.

unir-Enf sfr-.Aer es PATENT er Free.

TIMoTH-Y- J: vsH'aI\Te-1-Ian; or" BLUEVA Isnann,y ILLINcIs DIFFERENTIAL eLUTcH.y

Application filed- Marches, 192i; serial Iva. 456,243.

of the'. invention is. to

insure transmission of"l power .to bothi d riving wheels of amotor driven vehicle.: Motor vehicles equipped with the usual standard differential gearing are frequently stalled by mud, snowy or ice because of.. poorv traction conditions under aisingle wheel. The wheelmeeting with.. the least resistance receives the entire power` andxwilhspin while the other drivingl wheel` having; adequate Vtraction is inactive because no power: is transmitted to it. lfpowerunder these conditions were deliveredto thel wheell having the bettery traction; the vehicle could be movedf To, eliminate ars-.far` as-.possiblefthis trouble', various forms of direct driving mechanisms for the individual. wheels have beendevelopedbut these require a complete rearrangement off'the transmission systems in cars of the present type and very materially. increasethe costv of; production and the weight of the car. The mechanism forming the. present invention willy transmit power toibothlwheels at. alltimes with the exceptionl that no` powerf will be delivered to av wheel rotating faster than `the driving member.'A ,It will therefore be readily evident' tliataeither wheel may run ahead 4of .the drivingmember butvneither may. laghehind such member. Where one wheel is meetingL with tractionY resistance. andthe other is not, the powerA will then be delivered to both-:wheels in proportion to their. resistance.. rlfhe construction of the mechanism is suchthat it may7 be -usedl withY the standard axle.

Another important object of the inven- `tion istoprievent. skidding resulting from one wheellagging behind the driving mechanism.v

Further objects are to eliminate the need for brake equalizers, to insure the automatic engagement. andrelease off the driving4 elements at the proper time,fand in general to. pjroikzide a simplified and improved differ.- ential construction.`

The many` other objects and advantages of the invention will .bei better understoodby reference to the following specification when considered in connection with the accompanying drawings illustrating.. certain# selected embodiments thereof, in which Fig. 1 is a central vertical section ofk a differential embodying the invention complete.

Fig.` 2 is a transverse section on the line 2-2 of Fig.. 1, and; v f

`Fig. 3 is a similar section ofamodii'ed form of the invention.

Referring to the drawings, power istransmitted from the-engine byfthe usualdriving shaftY 5 which is providedat its outer cxtremity with a kbevel gearfdmeshing, with a. ring gear. -7k secured uponthe .central drivingidiskl 8. This disk is'..provided vwitlrcain blocks 9. projecting from oppcsiteY faces thereof 'and preferablyv integral withv the disk. Cylindricalg extensions 10 ofY tliese blocks, fit within corresponding- ,driven membersll to form bearingspxforl the disk. The driven members: fit..within the usual roller. bearings. 12 and aresplined .uponthe inner,v end of ftheir` respectivel axle v shafts 13.

Thel inner portionof. each` ofv the driven members 11 fforins, a drum 141.

vA cage 15 envelops each.. ofz the blocks 9 and, issupportedf by the ldisltS. Each. of

thesefcages consists of'spaced` rings 16 and 17. securedtogether by shouldered? pins 1S. The ring lfits over. the block and. the

. ring` 1i? its :over the extension .10 .in asimilar manner. Blocks` 19; and 20. are pivotal-ly mountedupon pins 18.011 opposite Asides of eachof theV caniblocls 9. Depressione-21. andV 22,-are formed in the outer. -face of the yblocks 19 andl 2O and hardened rollers 23 and 24.4rest within theseidepressions. rThese .depressions are so formedl that the rollers inthe inoperative position indicated in the drawings cannot simultaneously Contact with the bottomfof the .depressions and the inner faceof the d'r-umf14. i Y

The cage isi-free to .revolve about the driving` member on which, .it is mounted, and within the driven member. rThe relative rotation of the cages and the ydriving member is limited by the amount of clearance between the inner faces of the blocks 19 and 20 and the cam block 9.

A modified form of the. invention is shown in F ig. 3 of the drawings in which the blocks and 26 corresponding to the blocks 19 and 20 of the previous embodimentare not provided with binding rollers but depend wholly upon the interengagement of the outer faces of the blocks with the inner face of the drum 27. Zhen the differential is to be used on heavy draft vehicles, bosses ktion of the depression.

28 may be formed on the outer face of the blocks 25 and 26 to enter corresponding depressions 29 on the inner face of the drum. The drum engaging` blocks in any of the forms of the invention may be covered on their outer surfaces with any suitable friction material such as that used in lining brake bands.

In the operation of the device the main driving` shaft 5 is connected to the engine in the usual manner to provide both forward and reverse drive. Rotation of this shaft will cause a corresponding revolution of the driving disk 8 and the cam blocks il formed thereon or attached thereto. Viewing the structure as shown in F ig. 2, rotation of the cam block 9 in a clockwise direction will cause the faces 3G and 31 of this block to move into contact with the opposing faces of the blocks 19 and'20 and to rotate these blocks upon their respective pivots, likewise in a clockwise direction.

The rotation of these blocks 19 and 2O in this manner causes the outer faces 32 and 33 respectively'of these blocks to be forced into frictionalengagement with the inner face of the drum 14. Simultaneously with the moving of the block faces into contact with the drum, the rollers 24 are engaged by the drum and a counter-clockwise rotation of these rollers takes place which gradually forces the rollers into the narrow por- 'Ihe binding action increases until the driving and driven elements are rigidly locked together. A similar action takes place when the cam block is rotated in a counter-clockwise direction,

the binding action then taking place through the faces 34 and 35 of the blocks 19 and 2()y respectively and through the rollers 23.

When either wheel at any time tends to rotate'faster than the driving member, the drum connected to the aXle shaft of this wheel will cause the 'blocks engaging it to be rocked upon their pivots in the opposite direction to that in which they were moved to provide the initial locking. This counterrotation will only continue until the blocks strike the reverse face of the cam block.

v The rollers are then forced by the relative movement of the drum and blocks into the 'deep portion of the depressions and the blocks and rollers will assume the positions indicated in Fig. 2 of the drawings'. This disengagement will continue until the speed of the wheel tends to fall below ythat of the driving member. At this point the blocks will again be automatically forced into lock ing engagement and the wheel will be driven by the driving member.

It is .therefore evident that both driving wheels must rotate as rapidly as the driving. member but either or both may at any time rotate at a higher speed. If one wheel is not oering any resistance to the driving member for any reason, the power of the engine will be exerted through the other wheel. Thus when one wheel is operating upon a slippery surface and the other wheel is upon firm ground, the power will be transmitted to the latter, whereas with the ordinary differential gearing it would be conveyed to the former where it can perform little or no service. In turning a corner the power is transmitted to the inside driving wheel and the outside wheel runs free. As soon as the turn is completed, the free wheel will automatically engage and the driving action will take place through both wheels.

Brake action applied to either wheel will be transmitted to the driving member and the vehicle may be brought safely to a stop without the application of any braking action on the other wheel. the necessity for brake equalizers.

With the ordinary differential gearing skidding of the vehicle occurs frequentlyl on account of the lagging of one wheel and the accompanying increase in power applied to the other wheel. This is impossible with the present invention as neither' wheel may lag behind the driving member and` the power is exerted upon the slower ttlgrning wheel rather than upon the faster.

The control of Vthe blocks by the cage insures release of the drums at the proper times and absolutely prevents improper engagement.

The present construction is much more simple than the ordinary type of differential gearingl and the action is more smooth.

The term cage is used to define a construction comprising oppositely disposed side membersor rings connected by cross members, as distinguished from mere separate rings.

I am aware that many changes may be made in the form and arrangement of the various parts without departing from the spirit of my invention and I reserve the right to make all such as fairly fall within the scope of the following claims.V

I claim:

1. A device of the class described, comprising a revoluble driving disk, a revoluble driven drum, a cam formed on said disk, a cage mounted on said cam, blocks pivotally mounted in said cage and movable by This eliminates s said cam toward said drum, and rollers seated in the outer iace of each of said blocks adapted to frictionally lock said drum to said disk when said blocks are moved toward said drum by said cam.

2. A device of the class described, comprising a revoluble driving member, a revoluble driven member, a cage mounted on said driving member and revoluble therewith, a block interposed between said members, a roller seated in the outer Jface of said block, and means on said driving member for moving said block and said roller into frictional engagement with said driven member to lock said members together when said driving member is rotating more rapidly than said driven member.

3. A device of tlie class described, comprising a revoluble driving member, a revoluble driven member, a cage mounted on said driving member and revoluble therewith, a block interposed between said members, a pair of rollers seated in the Outer face of said block, and means on said driving member for shifting said block relative to said driven member to bring one of said rollers into frictional engagement with said driven member and lock said members together whensaid driving member is rotating more rapidly than said driven member.

4. A device of the class described, comprising a revoluble driving member, a revoluble driven member, a. cage mounted on said driven member and revoluble therewith, a block pivotally mounted intermediate its ends in said cage and having depressions in its outer face on opposite sides of the pivotal connection to receive rollers, a roller in each of said depressions, and means on said driving member for moving said block toward said driven member to bring one of said rollers into engagement with said driven member and cause said members to be locked together while said driving member is rotating more rapidly than said driven member.

Y TIMOTHY J. SHANAHAN. 

